The Largest Plant on Earth

An aspen grove used to be considered the biggest plant on Earth, but now that record has been broken.

The Shark Bay Posidonia australis. Credit: Rachel Austin via UWA, CBS News

Shark Bay, Western Australia. Scientists use genetic sequencing to study the local underwater plant life when they make a surprising discovery.

From a single seed, one seagrass individual has managed to grow to over 180 km (112 miles) in span. One single organism, confirmed to be so by the DNA sequencing, over 4500 years old. One specimen of Posidonia australis, created via a cloning process that produced many identical clones. Because they all share the same exact genome, they all belong to a single organism. The plant is by no means the oldest - a seagrass of the same genus in the Mediterranean is over 100,000 years old.

The seagrass of Shark Bay boasts an unusual, but not rare, genetic condition called polyploidy. Polyploidy describes the possession of multiple sets of chromosomes in an organism. Humans are diploid, meaning they have two sets. The Shark Bay individual has twice the number of chromosomes most members of its kind have - 40, rather than the usual 20. This polyploidy is what allows the organism to clone and spread over such a vast area.

Usually we think of trees when it comes to giant plants, but a seagrass? Who would've thought? You can read the full study here.